Briefcase



FIG. 1 is a perspective view showing my new design for a briefcase;

FIG. 2 is a top plan view thereof;

FIG. 3 is a bottom plan view thereof;

FIG. 4 is a left side elevational view thereof;

FIG. 5 is a right side elevational view thereof;

FIG. 6 is a front elevational view thereof;

FIG. 7 is a rear elevational view thereof;

FIG. 8 is a perspective view thereof; and,

FIG. 9 is a perspective view thereof in an open position.

The broken lines showing a shoulder strap in FIG. 8 and the interior in FIG. 9 form no part of the claimed design. 

The ornamental design for a briefcase, as shown and described. 